Many technicians are confused on how to really read a zener diode code. There are many types of code number indicated on it’s body. The look and shape of a zener diode sometimescan be mistaken to be a normal signal diode. To differentiate it, is by looking at the codenumber on it’s body- whether it [...]

If, for some reason, you can’t get an exact replacement for the transistor that you want to replace, you can refer to one of the transistor substitution guides or book, and try to identify a "near replacement". Beware, however. A substitution guide will sometimes list a replacement for your part, even though the two parts [...]